Code Playground

* {
	border: 0;
	box-sizing: border-box;
	margin: 0;
	padding: 0;
}
:root {
	--hue: 223;
	--bg: hsl(var(--hue),90%,90%);
	--fg: hsl(var(--hue),90%,10%);
	--primary1: hsl(var(--hue),90%,50%);
	--primary2: hsl(var(--hue),90%,80%);
	--trans-dur: 0.3s;
	font-size: calc(16px + (24 - 16) * (100vw - 320px) / (2560 - 320));
}
body {
	background-color: var(--bg);
	color: var(--fg);
	display: flex;
	font: 1em/1.5 sans-serif;
	height: 100vh;
	transition:
		background-color var(--trans-dur),
		color var(--trans-dur);
}
.pl,
.pl__surface,
.pl__prism {
	transform-style: preserve-3d;
}
.pl {
	margin: auto;
	position: relative;
	width: 16em;
	height: 16em;
	perspective: 64em;
}
.pl__surface,
.pl__prism,
.pl__side:nth-child(-n + 4),
.pl__side:before,
.pl__side--shadow-back1:after,
.pl__side--shadow-back2:after,
.pl__side--shadow-right1:after,
.pl__side--shadow-right2:after,
.pl__side--shadow-left1:after,
.pl__side--shadow-left2:after {
	--anim-dur: 12s;
	animation: spin var(--anim-dur) linear infinite;
}
.pl__surface {
	position: absolute;
	top: 60%;
	left: 50%;
	transform: translate(-50%,-50%) rotateX(45deg) rotateZ(45deg);
	width: 10em;
	height: 10em;
}
.pl__prism {
	animation-name: slide1;
	position: absolute;
	top: 0;
	left: 0;
	width: 4.5em;
	height: 4.5em;
	transform: translate3d(0,0,0) rotate(90deg);
}
.pl__prism:nth-child(2) {
	animation-name: slide2;
	transform: translate3d(5.5em,0,0) rotate(180deg);
}
.pl__prism:nth-child(3) {
	animation-name: slide3;
	transform: translate3d(0,5.5em,0) rotate(0);
}
.pl__prism:nth-child(4) {
	animation-name: slide4;
	transform: translate3d(5.5em,5.5em,0) rotate(-90deg);
	visibility: hidden;
}
.pl__side {
	overflow: hidden;
	transform: translate3d(0,0,4.5em);
}
.pl__side,
.pl__side:before,
.pl__side:after {
	position: absolute;
}
.pl__side,
.pl__side:before {
	top: 0;
	left: 0;
	width: 100%;
	height: 100%;
}
.pl__side:before,
.pl__side:after {
	content: "";
	display: block;
}
.pl__side:before {
	animation-name: none;
	background-color: hsl(0,0%,100%);
}
.pl__side:nth-child(1) {
	animation-name: side-top;
	transform-origin: 0 50%;
}
.pl__side:nth-child(2) {
	animation-name: side-back;
	transform: rotateX(90deg);
	transform-origin: 0 0;
}
.pl__side:nth-child(3) {
	animation-name: side-right;
	transform: rotateY(90deg);
	transform-origin: 100% 0;
}
.pl__side:nth-child(4) {
	animation-name: side-front;
	transform: rotateX(-90deg);
	transform-origin: 0 100%;
}
.pl__side:nth-child(5) {
	transform: rotateY(-90deg);
	transform-origin: 0 0;
}
.pl__side:nth-child(2):before,
.pl__side:nth-child(4):before {
	background-color: var(--primary1);
}
.pl__side:nth-child(3):before,
.pl__side:nth-child(5):before {
	background-color: var(--primary2);
}
.pl__side--shadow-back1:after,
.pl__side--shadow-back2:after,
.pl__side--shadow-right1:after,
.pl__side--shadow-right2:after,
.pl__side--shadow-left1:after,
.pl__side--shadow-left2:after {
	background-color: hsla(var(--hue),90%,50%,0.5);
	top: 0;
	left: 0;
	width: 100%;
	height: 75%;
}
.pl__side--shadow-right2:after,
.pl__side--shadow-left1:after,
.pl__side--shadow-left2:after {
	width: 75%;
	height: 100%;
}
.pl__side--shadow-right2:after {
	animation-name: shadow-right2;
	right: 0;
	left: auto;
}
.pl__side--fade1:before {
	animation-name: fade1;
}
.pl__side--fade2:before {
	animation-name: fade2;
}
.pl__side--fade3:before {
	animation-name: fade3;
}
.pl__side--fade4:before {
	animation-name: fade4;
}
.pl__side--shadow-back1:after {
	animation-name: shadow-back1;
}
.pl__side--shadow-right1:after {
	animation-name: shadow-right1;
}
.pl__side--shadow-left1:after {
	animation-name: shadow-left1;
}
.pl__side--shadow-back2:after {
	animation-name: shadow-back2;
}
.pl__side--shadow-left2:after {
	animation-name: shadow-left2;
}
.pl__prism:nth-child(1) .pl__side {
	animation-delay: calc(var(--anim-dur) * 0.25);
}
.pl__prism:nth-child(2) .pl__side {
	animation-delay: calc(var(--anim-dur) * 0.5);
}
.pl__prism:nth-child(4) .pl__side {
	animation-delay: calc(var(--anim-dur) * 0.75);
}

/* Dark theme */
@media (prefers-color-scheme: dark) {
	:root {
		--bg: hsl(var(--hue),90%,10%);
		--fg: hsl(var(--hue),90%,90%);
	}
}

/* Animations */
@keyframes fade1 {
	from {
		animation-timing-function: steps(1,end);
		background-color: var(--primary1);
	}
	62.5%,
	75% {
		animation-timing-function: linear;
		background-color: var(--primary2);
	}
	to {
		background-color: var(--primary1);
	}
}
@keyframes fade2 {
	from {
		background-color: var(--primary2);
	}
	25%,
	50% {
		animation-timing-function: steps(1,start);
		background-color: var(--primary1);
	}
	to {
		background-color: var(--primary2);
	}
}
@keyframes fade3 {
	from, 25% { background-color: var(--primary2); }
	50%, to { background-color: var(--primary1); }
}
@keyframes fade4 {
	from, 50% { background-color: var(--primary2); }
	75%, to { background-color: var(--primary1); }
}
@keyframes shadow-back1 {
	from {
		transform: translate(0);
	}
	12.5% {
		animation-timing-function: steps(1,end);
		transform: translate(0,-100%);
	}
	87.5% {
		animation-timing-function: linear;
		transform: translate(0,0);
	}
	to {
		transform: translate(-122.22%,0);
	}
}
@keyframes shadow-back2 {
	from, 25% { transform: translateY(0); }
	37.5%, to { transform: translateY(-100%); }
}
@keyframes shadow-right1 {
	from {
		animation-timing-function: steps(1,end);
		visibility: hidden;
		transform: translateY(0);
	}
	62.5%,
	75% {
		animation-timing-function: linear;
		visibility: visible;
		transform: translateY(0);
	}
	87.5%,
	to {
		visibility: visible;
		transform: translateY(-100%);
	}
}
@keyframes shadow-right2 {
	from, 37.5% { transform: translateY(0); }
	50%, to { transform: translateY(-122.22%); }
}
@keyframes shadow-left1 {
	from {
		animation-timing-function: steps(1,end);
		visibility: hidden;
	}
	62.5%,
	to {
		visibility: visible;
	}
}
@keyframes shadow-left2 {
	from, 50% { transform: translateX(0); }
	62.5%, to { transform: translateX(-100%); }
}
@keyframes side-top {
	from { transform: translate3d(0,0,4.5em) scaleX(1); }
	12.5% { transform: translate3d(0,0,4.5em) scaleX(2.2222); }
	25%, to { transform: translate3d(0,0,4.5em) scaleX(1); }
}
@keyframes side-back {
	from { transform: rotateX(90deg) scaleX(1); }
	12.5% { transform: rotateX(90deg) scaleX(2.2222); }
	25%, to { transform: rotateX(90deg) scaleX(1); }
}
@keyframes side-right {
	from { transform: rotateY(90deg) translate3d(0,0,0); }
	12.5% {transform: rotateY(90deg) translate3d(0,0,5.5em); }
	25%, to {transform: rotateY(90deg) translate3d(0,0,0); }
}
@keyframes side-front {
	from { transform: rotateX(-90deg) scaleX(1); }
	12.5% { transform: rotateX(-90deg) scaleX(2.2222); }
	25%, to { transform: rotateX(-90deg) scaleX(1); }
}
@keyframes slide1 {
	from, 37.5% { transform: translate3d(0,0,0) rotate(90deg); }
	50%, to { transform: translate3d(0,0,0) rotate(90deg) translate3d(5.5em,0,0); }
}
@keyframes slide2 {
	from, 62.5% { transform: translate3d(5.5em,0,0) rotate(180deg); }
	75%, to { transform: translate3d(5.5em,0,0) rotate(180deg) translate3d(5.5em,0,0); }
}
@keyframes slide3 {
	from,
	12.5% {
		transform: translate3d(0,5.5em,0);
	}
	25% {
		transform: translate3d(0,5.5em,0) translate3d(5.5em,0,0);
		visibility: visible;
	}
	87.5%,
	to {
		transform: translate3d(0,5.5em,0) translate3d(5.5em,0,0);
		visibility: hidden;
	}
}
@keyframes slide4 {
	from {
		animation-timing-function: steps(1,end);
		transform: translate3d(5.5em,5.5em,0) rotate(-90deg);
		visibility: hidden;
	}
	75%,
	87.5% {
		animation-timing-function: linear;
		transform: translate3d(5.5em,5.5em,0) rotate(-90deg);
		visibility: visible;
	}
	to {
		transform: translate3d(5.5em,5.5em,0) rotate(-90deg) translate3d(5.5em,0,0);
	}
}
@keyframes spin {
	from { transform: translate(-50%,-50%) rotateX(45deg) rotateZ(45deg); }
	to { transform: translate(-50%,-50%) rotateX(45deg) rotateZ(405deg); }
}

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